An exhaust gas recirculation (EGR) valve generally has a pintle positioned by an actuator to control recirculation of exhaust gases in an engine. The actuator retracts the pintle from a seat to increase recirculation of exhaust gases, and advances the pintle toward the seat to reduce recirculation of exhaust gases. The seat is incorporated in a base that mounts the EGR valve on the engine manifold. The EGR valve may be adaptable to a variety of engine manifolds by varying the actuator characteristics, the shape of the pintle and seat, and the design of the mounting base.
Variations in actuator characteristics and the shape of the pintle and seat usually may be accommodated without substantial change in the equipment employed to assemble EGR valves. However, variations in the design of the mounting base are not readily accommodated. Because the seat is incorporated in the base, the pintle and its actuator must be installed on the base in order to align the pintle with the seat.
Accordingly, EGR valves are assembled from the base up, and the assembly equipment has a pallet that receives the base during installation of the pintle and actuator. The assembly equipment places height and width restrictions on the design of the base, requires a change in the design of the pallet with a change in the design of the mounting base, and requires a change in the height of the tooling with a change in the height of the base.
This invention provides an EGR valve that allows variations in the design of an EGR valve mounting base to be accommodated without substantial change in the assembly equipment.
This new EGR valve has a seat formed in a member that is secured to the actuator independently of the base and that can accommodate a wide variety of base designs. With this new EGR valve, the assembly equipment may have a pallet to receive the seat member during installation of the pintle and actuator, and the base may be added in a separate operation. With this new EGR valve, therefore, the assembly equipment need not impose height and width restrictions on the design of the base, need not require a change in the design of the pallet with a change in the design of the base, and need not require a change in the height of the tooling with a change in the height of the base.
It will be appreciated that this new EGR valve may be assembled entirely independently of the base, may be used with a base integrated in the engine manifold, and may be warehoused without a base.
The details as well as other features and advantages of a preferred embodiment of this new EGR valve are set forth in the remainder of the specification and are shown in the drawing.